In that case, I would suggest checking first to see if you can even obtain two qualifying composites. You need at least two out of Total Achievement, Total Reading, Written Expression, or Mathematics.
E.g., for Total Reading, you need to have four subtests: reading comprehension, word reading, pseudoword decoding, and oral reading fluency. For Written Expression, you need alphabet writing fluency, sentence composition, and spelling. For Mathematics, you need math problem solving and numerical operations.
Total Achievement should be a little bit easier, because at his age, that can be obtained from just five subtests: listening comprehension, oral expression, early reading skills, math problem solving, and alphabet writing fluency--this would also be a real age-normed standard score, unlike the others, which would be grade-normed, using a placeholder grade to derive above-level standard scores.
If you'd like to pm me, we can discuss this further using your actual subtest data.
